Check on this video and notice there are a lot of connections using uncovered wire. Why not use covered wire or something? Any particular reason?
Why Not Use Shielded Wiring?
- Thread starter SavageRiffer
- Start date
paulyc":2ox2h7v5 said:
Doesn't insulated wire usually have shielding? Isn't the shielding that metallic film inside the wire casing?
No, insulated wire is thin covered wire with a specific coloring on it (but no shield). Shielded wire (cable really) has the hot inside a shield (like guitar cable). Shielded cable is used in an amp leading from the input jacks. As screwy as it sounds, sometimes only ONE END of the shield is connected to anything in the amp either...
In the video above there is also uncovered wire running between the speaker jacks, and sometimes it's run across the backs of the pots and connected to ground depending on the design of the amp (it can be used other places too).
In the video above there is also uncovered wire running between the speaker jacks, and sometimes it's run across the backs of the pots and connected to ground depending on the design of the amp (it can be used other places too).
GuitarGuyLP
Active member
If you ground both ends of a shielded wire you basically make an antenna. After the first gain stage you don't need shielded wire, only the high impedance signal from the guitar is really susceptible to noise. I have also seen shielding up to the gain pot in high gain amps, but it is not always needed.
FourT6and2
Well-known member
OP, I didn't watch the video, but from you description, a lot of uncovered (buss) wire is for grounding. As such, no shielding or insulation is needed. In the photos below you can see both types (buss and coax). The buss wire is used to ground all the pots and jacks and whatnot. The buss wire on the tube sockets is used for the heaters and doesn't need insulation or shielding either.
Grounding both ends of the shield negate the benefits of using shielded cable in the first place.
Sometimes shielded cable is used for specific purposes. For example, it's used here from input jack to first gain stage, on the gain pots, and the FX loop send/return.
paulyc":3mdydcwf said:
Grounding both ends of the shield negate the benefits of using shielded cable in the first place.
Sometimes shielded cable is used for specific purposes. For example, it's used here from input jack to first gain stage, on the gain pots, and the FX loop send/return.
Thanks, some good information. It was the noise and corrosion factor that I was particularly wondering about. Given that amps are often in sweaty clubs and endure years of heat and humidity, it would seem that an insulated wire would be much more resistant to corrosion. However, I have seen the old pictures of Marshalls and Fenders, so I know they last a real long time. I'm seriously thinking about building an 18w Marshall or a Fender 57 Deluxe clone kit, but of course, I'll end up buying whatever has the best and most comprehensive instructions.
FourT6and2
Well-known member
SavageRiffer":dsn7vghd said:
You'll be fine. I wouldn't worry about corrosion in this type of application.
FourT6and2":3avafsfb said:
I wasn't worried about it, just wondering why the choice for bare wire is made over insulated or shielded. Thanks for all the info.
FourT6and2
Well-known member
SavageRiffer":3nhrp596 said:
Because it's easier. When you are running a ground buss, you don't want to spend an hour or two isolating 10 different points on the wire and stripping just those spots to connect components. You just run a length of buss wire and you can connect a bunch of things to it along its length.
It's also cheaper. Shielded coax is comparatively expensive. And you'd be wasting shielded wire on nothing but a ground connection that doesn't need to be shielded.